add helpers for typing; fix self attr; fix SELF_TYPE is_exist

assignments/PA4/bad_inherit.cl

@@ -34,7 +34,7 @@ class Err3 inherits String {};
 class Err3 inherits Bool {};
 class Err4 inherits Err3 {};*)
 class Err4 inherits Ok1 {
-    bye: Bool <- 10;
+    bye: NOEXIST <- 10;
     hello(a: TT) : NOEXIST { new Object };
 };
 
@@ -69,6 +69,7 @@ class DummyMain {
 class Main inherits DummyMain {
     attr1: Bool <- (new Err5).hello();
     attr2: Int <- (new Err5).bye();
+    self(): SELF_TYPE { new SELF_TYPE };
     main(): Object {
         {
             let x:Int in {
@@ -79,7 +80,7 @@ class Main inherits DummyMain {
         }
     };
 
-    main: Bool <- true;
+    main: Bool <- true + false;
 };
 
 class Err5 {

assignments/PA4/cool-tree.h

@@ -28,6 +28,7 @@ public:
 };
 
 
+class ClassTable;
 // define simple phylum - Class_
 typedef class Class__class *Class_;
 
@@ -35,6 +36,7 @@ class Class__class : public tree_node {
 public:
    tree_node *copy()		 { return copy_Class_(); }
    virtual Class_ copy_Class_() = 0;
+   virtual void semant(ClassTable*) = 0;
 
 #ifdef Class__EXTRAS
    Class__EXTRAS
@@ -49,6 +51,7 @@ class Feature_class : public tree_node {
 public:
    tree_node *copy()		 { return copy_Feature(); }
    virtual Feature copy_Feature() = 0;
+   virtual void semant(Class_, ClassTable*) = 0;
 
 #ifdef Feature_EXTRAS
    Feature_EXTRAS
@@ -164,7 +167,7 @@ public:
    Symbol get_name() const { return name; }
    Symbol get_parent() const { return parent; }
    Features get_features() const { return features; }
-   void semant();
+   void semant(ClassTable*);
 
 #ifdef Class__SHARED_EXTRAS
    Class__SHARED_EXTRAS
@@ -196,6 +199,7 @@ public:
    Formals get_formals() const { return formals; };
    Symbol get_return_type() const { return return_type; };
    Expression get_expr() const { return expr; };
+   void semant(Class_, ClassTable*);
 
 #ifdef Feature_SHARED_EXTRAS
    Feature_SHARED_EXTRAS
@@ -224,6 +228,7 @@ public:
    Symbol get_name() const { return name; };
    Symbol get_type_decl() const { return type_decl; };
    Expression get_init() const { return init; };
+   void semant(Class_, ClassTable*);
 
 #ifdef Feature_SHARED_EXTRAS
    Feature_SHARED_EXTRAS

assignments/PA4/semant.cc

@@ -5,9 +5,9 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
-#include <utility>
 #include <vector>
 #include <queue>
+#include <memory.h>
 #include "cool-tree.h"
 #include "semant.h"
 #include "utilities.h"
@@ -110,14 +110,10 @@ ClassTable::ClassTable(Classes classes) : semant_errors(0) , error_stream(cerr)
     }
 
     /* second scan: check base class inheritable */
-    auto sym_Bool = idtable.lookup_string("Bool");
-    auto sym_Int = idtable.lookup_string("Int");
-    auto sym_String = idtable.lookup_string("String");
-    
     for (auto class_i : _class_vec) {
         auto sym_parent = class_i->get_parent();
         // Cool has restrictions on inheriting from the basic classes
-        if ( sym_parent == sym_Bool || sym_parent == sym_Int || sym_parent == sym_String) {
+        if ( sym_parent == Bool || sym_parent == Int || sym_parent == Str) {
             semant_error(class_i) <<  "Class " << class_i->get_name()
                 << " cannot inherit class " << sym_parent << ".\n";
         }
@@ -157,9 +153,9 @@ ClassTable::ClassTable(Classes classes) : semant_errors(0) , error_stream(cerr)
 void ClassTable::symtab_dump(Symbol class_name) {
     std::cerr << "SymTab of " << class_name << "\n";
     std::cerr << "M(" << class_name << ") =";
-    symtab_met[class_name]->dump();
+    _symtab_met[class_name]->dump();
     std::cerr << "O(" << class_name << ") =";
-    symtab_obj[class_name]->dump();
+    _symtab_obj[class_name]->dump();
     std::cerr << "--------\n\n";
 }
 
@@ -168,7 +164,7 @@ Symbol ClassTable::symtab_object_lookup_parent(Symbol class_name, Symbol object_
     auto class_node = name_to_node[class_name];
     auto parent_node= class_node->parent;
     while (parent_node) {
-        auto result = symtab_obj[parent_node->get_class()->get_name()]->probe(object_name);
+        auto result = _symtab_obj[parent_node->get_class()->get_name()]->probe(object_name);
         // only need to lookup in the top scope, because attributes all reside in top scope
         if (result) return result;
         parent_node = parent_node->parent;
@@ -181,7 +177,7 @@ method_class* ClassTable::symtab_method_lookup_parent(Symbol class_name, Symbol
     auto class_node = name_to_node[class_name];
     auto parent_node= class_node->parent;
     while (parent_node) {
-        auto result = symtab_met[parent_node->get_class()->get_name()]->probe(method_name);
+        auto result = _symtab_met[parent_node->get_class()->get_name()]->probe(method_name);
         // only need to lookup in the top scope, because attributes all reside in top scope
         if (result) return result;
         parent_node = parent_node->parent;
@@ -191,8 +187,6 @@ method_class* ClassTable::symtab_method_lookup_parent(Symbol class_name, Symbol
 
 void ClassTable::install_all_features() {
     /* fourth scan: gather attr and method definition */
-    auto sym_Main = idtable.lookup_string("Main");
-    auto sym_main = idtable.lookup_string("main");
     class__class* class_Main = nullptr;
     method_class* method_main = nullptr; // main in class Main
     std::queue<ClassGraphNode*> _iter_queue;
@@ -208,13 +202,13 @@ void ClassTable::install_all_features() {
         }
         auto cur_class = cur_node->get_class();
         auto cur_name = cur_class->get_name();
-        if (cur_name == sym_Main) {
+        if (cur_name == Main) {
             class_Main = cur_class;
         }
-        symtab_met[cur_name] = new SymbolTable<Symbol, method_class>;
+        _symtab_met[cur_name] = new SymbolTable<Symbol, method_class>;
-        symtab_obj[cur_name] = new SymbolTable<Symbol, Entry>;
+        _symtab_obj[cur_name] = new SymbolTable<Symbol, Entry>;
-        symtab_met[cur_name]->enterscope();
+        _symtab_met[cur_name]->enterscope();
-        symtab_obj[cur_name]->enterscope();
+        _symtab_obj[cur_name]->enterscope();
 
         auto cur_features = cur_class->get_features();
         for (auto j = cur_features->first(); cur_features->more(j); j = cur_features->next(j)) {
@@ -223,7 +217,11 @@ void ClassTable::install_all_features() {
             if (typeid(*cur_feature) == typeid(attr_class)) {
                 auto cur_attr = static_cast<attr_class*>(cur_feature);
                 // std::cerr << "attr " << cur_attr->get_name() << "\n";
-                if (symtab_obj[cur_name]->lookup(cur_attr->get_name()) != nullptr) {
+                if (cur_attr->get_name() == self) {
+                    semant_error(cur_class->get_filename(), cur_attr)
+                        << "\'self\' cannot be the name of an attribute.\n";
+                }
+                else if (_symtab_obj[cur_name]->lookup(cur_attr->get_name()) != nullptr) {
                     semant_error(cur_class->get_filename(), cur_attr) << "Attribute " << cur_attr->get_name() 
                                             << " is multiply defined.\n";
                 }
@@ -233,13 +231,13 @@ void ClassTable::install_all_features() {
                                             << " is an attribute of an inherited class.\n";
                 }
                 else {
-                    symtab_obj[cur_name]->addid(cur_attr->get_name(), cur_attr->get_type_decl());
+                    _symtab_obj[cur_name]->addid(cur_attr->get_name(), cur_attr->get_type_decl());
                 }
             }
             else if (typeid(*cur_feature) == typeid(method_class)) {
                 auto cur_method = static_cast<method_class*>(cur_feature);
                 // std::cerr << "method " << cur_method->get_name() << "\n";
-                if (symtab_met[cur_name]->lookup(cur_method->get_name()) != nullptr) {
+                if (_symtab_met[cur_name]->lookup(cur_method->get_name()) != nullptr) {
                     semant_error(cur_class->get_filename(), cur_method) << "Method " << cur_method->get_name() 
                                             << " is multiply defined.\n";
                 } 
@@ -292,8 +290,8 @@ void ClassTable::install_all_features() {
                     }
                     if (!_error_flag) {
                         // std::cerr << "method done " << cur_method->get_name() << "\n";
-                        symtab_met[cur_name]->addid(cur_method->get_name(), cur_method);
+                        _symtab_met[cur_name]->addid(cur_method->get_name(), cur_method);
-                        if (class_Main != nullptr && cur_name == sym_Main && cur_method->get_name() == sym_main) {
+                        if (class_Main != nullptr && cur_name == Main && cur_method->get_name() == main_meth) {
                             // main in class Main
                             method_main = cur_method;
                         }
@@ -471,7 +469,28 @@ ostream& ClassTable::semant_error()
     return error_stream;
 } 
 
+/*
+* Query the Inheritance Graph if T1 <= T0
+* Note: if T1 inherits from(or is) T0, then T1 <= T0
+*/
+bool ClassTable::conform(Symbol T1, Symbol T0) const {
+    if (T1 == T0) return true;
+    auto cur_node_itr = name_to_node.find(T1);
+    assert(cur_node_itr != name_to_node.end());
+    auto cur_node = cur_node_itr->second;
+    while (cur_node) {
+        if (cur_node->get_class()->get_name() == T0) {
+            return true;
+        }
+        cur_node = cur_node->parent;
+    }
+    return false;
+}
 
+bool ClassTable::class_exist(Symbol class_id) const {
+    if (class_id == SELF_TYPE) return true;
+    return name_to_node.find(class_id) != name_to_node.end();
+}
 
 /*   This is the entry point to the semantic checker.
 
@@ -502,7 +521,13 @@ void program_class::semant()
     classtable->install_all_features();
     /* Top down type checking */
     for (auto class_i : classtable->class_vec()) {
-        class_i->semant();
+        // before we enter a class, add self:SELF_TYPE to its scope
+        // TODO: Maybe integrate this into last scan
+        classtable->symtab_obj(class_i->get_name())->enterscope();
+        classtable->symtab_obj(class_i->get_name())->addid(self, SELF_TYPE);
+        class_i->semant(classtable);
+        // leave scope
+        classtable->symtab_obj(class_i->get_name())->exitscope();
     }
 
     if (classtable->errors()) {
@@ -511,7 +536,36 @@ void program_class::semant()
     }
 }
 
-void class__class::semant()
+void class__class::semant(ClassTable * classtable)
+{
+    for (auto i = features->first(); features->more(i); i = features->next(i)) {
+        auto cur_feature = features->nth(i);
+        cur_feature->semant(this, classtable);
+    }
+}
+
+void attr_class::semant(Class_ cur_class, ClassTable * classtable)
+{
+    if (typeid(*init) == typeid(no_expr_class)) {
+        /*
+        * Attr-No-Init: 
+        *   Check if Declared Type is defined, if so, do nothing because already
+        *   in AST; else, error report and set its type to Object
+        */
+        if (!classtable->class_exist(type_decl)) {
+            classtable->semant_error(cur_class->get_filename(), this)
+                << "Class " << type_decl
+                << " of attribute " << name
+                << " is undefined.\n";
+            this->type_decl = Object;
+        }
+    }
+    else {
+        // Attr-Init
+    }
+}
+
+void method_class::semant(Class_ cur_class, ClassTable * classtable)
 {
 
 }

assignments/PA4/semant.h

@@ -145,19 +145,26 @@ private:
   std::map<Symbol, ClassGraphNode*> name_to_node;
 
   // The symbol table only stores pointers, so DATA type defined here dont need a ptr
-  std::map<Symbol, SymbolTable<Symbol, Entry>* > symtab_obj;
+  std::map<Symbol, SymbolTable<Symbol, Entry>* > _symtab_obj;
-  std::map<Symbol, SymbolTable<Symbol, method_class>*> symtab_met;
+  std::map<Symbol, SymbolTable<Symbol, method_class>*> _symtab_met;
 
   // Actually, it makes things easier to keep a list-shape copy of classes
   std::vector<class__class*> _class_vec;
 
 public:
   ClassTable(Classes);
+  /* helpers */
   void install_all_features();
   void symtab_dump(Symbol);
   Symbol symtab_object_lookup_parent(Symbol, Symbol);
   method_class* symtab_method_lookup_parent(Symbol, Symbol);
+  bool conform(Symbol, Symbol) const;
+  bool class_exist(Symbol) const;
+  /* wrappers */
   std::vector<class__class*>& class_vec() { return _class_vec; }
+  SymbolTable<Symbol, Entry>* symtab_obj(Symbol class_id) { return _symtab_obj[class_id]; };
+  SymbolTable<Symbol, method_class>* symtab_met(Symbol class_id) { return _symtab_met[class_id]; };
+
   int errors() { return semant_errors; }
   ostream& semant_error();
   ostream& semant_error(Class_ c);